The present invention relates to a method for the navigation of a vehicle, wherein the vehicle includes a course reference device which furnishes a course signal which represents the direction of the vehicle with reference to an earthbound coordinate system; a longitudinal movement sensor for detecting longitudinal movement of the vehicle and generating a longitudinal movement signal; a position computer for calculating vehicle position data, segregated into north and east position values, from signals generated by the course reference device and the longitudinal movement sensor; display means connected to the position computer for displaying vehicle position data calculated by the position computer; and input means including manual input means and signal receiving means for providing, respectively, additional position data and course, velocity and path data for navigation support.
A navigation system of this type is described in German Pat. No. 3,033,279. Such a navigation system is used for determining the position of a vehicle in a grid coordinate system, namely the UTM (Universal Transverse Mercator) grid system. The vehicle position is determined from the course angle furnished by a course reference device with reference to the UTM grid coordinate system and from distance signals obtained by integration of the vehicle speed. Position errors occurring during travel, which have no linear relationship to the path traveled or the travel time, are eliminated in that, at the moment at which the vehicle is at a known point in the terrain, a comparison is made between the displayed location and the actual location of the vehicle, a path adaptation factor is determined and the course angle is corrected.
However, it has been found to be desirable to correct the indicated positon not only when a known terrain point is reached, but also to make a correction of the displayed data continuously and in a discrete-time manner.